The Outside Waistband holster is designed to fit the Arex Delta L, Delta M, and Delta X pistol with the Streamlight TLR-7 X or TLR-7 A light mounted to the pistol. The holster retention is on the light itself and not the pistol, which means the holster will not work without the light mounted on the firearm. Red Dot/RMR sight must not overhang the edge of the slide or be wider than the slide to fit the profile of the holster. Product Details: The data sheet for the Streamlight TLR-7 X can be found here. Our holsters for the Arex Delta are vacuum formed with a precision machined mold designed from a CAD model of the actual firearm and light.  Each holster is formed, trimmed, and folded in-house. Final fit and function tests are done with the actual pistol and light to ensure the holster fits the gun/light combination and has the correct amount of retention. The holster's retention is easily adjusted so that the fit can be set to your personal preference. Features: Adjustable retention  High sweat shield standard Holster profile cut for red dot and RMR sights Made from .080" thick thermoplastic for durability Proudly Made in the USA Our Belt Attachment Blog Article explaining the different options can be found here: 4BROS Four Brothers Holsters Outside Waistband Attachments Explained Magazine Pouches for these models can be found here: Arex Delta 9mm IWB Magazine Carrier Arex Delta 9mm OWB Magazine Carrier  *We strongly suggest you apply a removable thread locker to each screw of your holster after you receive it to prevent lost screws while the holster is in use.